Đo nhiệt độ P16

Temperature Measurement of Fluids Low Velocity Gas Contact sensors Assume that a gas, with a temperature, T., flows in a tube with a flow-velocity below about 20 m/s, as shown in Figure 17.1(a) . In the tube there is a sheathed sensor, whose sensitive part, at temperature, TT , is placed in the sheath bottom. This case corresponds to a thermocouple with the measuring junction welded into the sheath bottom . Also let the temperature ofthe internal surface ofthe tube wall be TW , while the length to diameter ratio of the sensor sheath is assumed to be so large that...